console.log(new Blob(['foo']));  
// Blob {size: 3, type: ""}

console.log(new Blob(['{"a": "b"}'], { type: 'application/json' }));
// {size: 10, type: "application/json"}

console.log(new Blob(['<p>Foo</p>', '<p>Bar</p>'], { type: 'text/html' }));
// {size: 20, type: "text/html"}
